I cannot figure out how to install the KDE Neon 5.18.4 user edition to a SSD with a GPT partitioning with UEFI boot.
I have tried to search the forum and the Web but I cannot find help. Some ended up installing the legacy BIOS boot and a video in the YouTube shows different installer that I am experiencing. https://www.youtube.com/watch?v=7oHDshLwyys

I have an Asus TUF-B450 Pro Gaming Mobo and another OS (Kubuntu 19.10) on a HDD (/dev/sda) with GPT & UEFI boot.
I have added a SSD (/dev/nvme0n1) for the KDE Neon, that I want to try. I will want a dual boot.

I have created the GPT partitioning table and the following partitions with gdisk on Kubuntu (1: efi parition "ef00",2: linux swap, 3:ext4, 4,ext4).

When I am in the disk setup I would like to use these (separate) paritions as opposed letting the installer to make only one partition. I select the "Manual"-option.
However, the installer does not recognize any of the partition types ! They show all "unknown"
In particular, I cannot create the efi-partition even if I tried to modify/change the current partitions. The FAT32 is mounted only as /dos or /windows. In the video referred above the drop down menu shows also an option "EFI system partition" that does not exist in my case. Also the option "reserved BIOS boot area" does not sound right. I am reading that it refers to BIOS booting.

How can I install the KDE Neon with Uefi (dual)boot on my SSD ?

BR

EDIT
What has probably happened is that the installation media booted in the legacy BIOS mode as the secure boot is enabled by default on this mother board. Most likely I was able to drop the Kubuntu in the UEFI mode as the Kubuntu installer was signed by Canonical. As my KDE Neon installer is in the BIOS mode it does not allow me to install the OS in UEFI.

I do not fully understand my options and some help would be appreciated. I believe I have two options to go:

1. Disable the Secure boot

This is not so easy as it sounds. There is no simple GUI allowing me to disable it. Possibly, I can edit some keys but I do not fully understand the risks and consequences. I need some clear and reliable instructions not to brick my mobo. I am not sure what happens if I edit some keys and do something wrong ? Am I able to recover ? I am not concerned about installing Windows. I am using only Linux on this PC.

2. Let the KDE Neon install in the legacy BIOS mode

Will the KDE Neon installer detect the Kubuntu that was installed in the UEFI mode?

If I install now in BIOS mode will I be later able to upgrade to UEFI? Say, with the Kubuntu installation media that I still have? Is there any real reasons to upgrade to UEFI anyway?

I will want to have a multiboot system to ease my migrations from one system to another. I am using dedicated disks for each system. This also why I partition my data separately and do not want to let the installer to use the whole disk. I believe that using legacy BIOS is not the best option going forward.

If I did choose this option and installed the KDE Neon in the BIOS mode I believe I need to create one more partition for the "BIOS boot area" and select it during the install. I guess I can reduce the partition I reserved for the EFI-partition. Am I able to do this in the KDE Neon installer or do I need to use gdisk to do it ?

EDIT 2

It looks like I got the issue resolved. The problem seemed to be a firmware setting on the Asus motherboard. The boot mode for the storage devices was defaulted "legacy" which caused the KDE Neon to boot in the legacy BIOS mode. This, in turn, prevented the UEFI instalation. I changed the firmware setting to "UEFI driver first" also for the "storage devices". After that the KDE Neon installer booted in the UEFI mode and recognized my GPT partitions ok. The installation was successful after that.